It is common in the restaurant, food service, and beverage industry to use automatic dishwashers that accept a standard dishwasher rack for cups and glasses. Generally speaking, a conventional dishwasher rack is in the shape of a rectangular (typically square) box with a bottom panel and four sidewalls, but an open top. Within this box is a rectangular grid of walls or slats, defining a matrix of compartments into which glasses or cups may be inserted, typically having paddle-shaped walls that extend higher in the center thereof than at the ends so as to protect glasses placed in the compartments and yet permit water to flow through a substantial portion of the dividers. The grid typically is molded so as to be integral with the sidewalls and includes a multiplicity of shapes and number of compartments and sizes to fit a wide variety of sizes of glasses. For example two common rack configurations contain four or five rows and columns of compartments (i.e., 4×4 or 5×5). The compartments of the adjacent rows and columns typically are nested with one another, so that adjacent compartments share a wall.
Different racks with different sized compartments commonly are used to most closely match the diameter of the glasses or cups being washed. However, a conventional dishwasher rack typically is 19.72″×19.72″ and is divided into 16 compartments (4×4), with each compartment able to hold a glass with a diameter of 4.25 inches or less, or is divided into 25 compartments (5×5), with each compartment able to hold a glass with a diameter of 3.35 inches or less, e.g., as described in U.S. Pat. Nos. 2,741,392, 3,283,915, 3,442,397, 3,584,744, 3,009,579, 3,245,548, 3,482,707 and 4,621,739, as well as in U.S. Patent Application Publication No. 2002/0117461. The forgoing sizes given for the compartments in a dishwasher rack are just examples of commonly used configurations, it being understood that many compartments having many other configurations, in terms of number of compartments and sizes of compartments, are available and useful for washing cups and glasses.
A conventional dishwasher rack can consist of a single component (which can be referred to as a base component) having the foregoing configuration. Alternatively, one or more “rack extenders”, e.g., as discussed and/or shown in U.S. Pat. Nos. D399,614, D400,321 and in U.S. Patent Application Publication Nos. 2003/0178378 and 2002/0117461 can be attached to the base component to increase the height or to change the number, the size or the configuration of the interior compartments of the rack, and thereby accommodate taller glasses or cups or such different sizes or configurations. These one or more extenders are stacked one on top of the base component and then on top of each other, with all the components typically fitting together and being held in place by a number of interlocking pins and receiving sockets, e.g., as described and/or shown in U.S. Pat. Nos. 3,283,915, 3,584,744, D399,614 and D400,321, as well as in U.S. Patent Application Publication Nos. 2002/0117461 and 2003/0178378. A rack extender typically is similar to the base unit in cross-section, having the same (or roughly the same) length and width and a matching internal grid, but has both an open bottom and an open top. Such dishwasher racks provide for easy transport of cups and glasses and work well in many cases.